text: #coding:utf-8
  #
  # id:           bugs.core_1510
  # title:        Bad XSQLVAR [NULL flags] for (2*COALESCE(NULL,NULL))
  # decription:   
  # tracker_id:   CORE-1510
  # min_versions: ['2.1.7']
  # versions:     3.0
  # qmid:         None
  
  import pytest
  from firebird.qa import db_factory, isql_act, Action
  
  # version: 3.0
  # resources: None
  
  substitutions_1 = [('^((?!sqltype).)*$', ''), ('[ ]+', ' '), ('[\t]*', ' '), ('charset:.*', '')]
  
  init_script_1 = """"""
  
  db_1 = db_factory(page_size=4096, sql_dialect=3, init=init_script_1)
  
  test_script_1 = """
      set sqlda_display;
      select 2*COALESCE(NULL,NULL) from RDB$DATABASE;
      select 2*IIF(NULL is NULL, NULL, NULL) from RDB$DATABASE;
    """
  
  act_1 = isql_act('db_1', test_script_1, substitutions=substitutions_1)
  
  expected_stdout_1 = """
      01: sqltype: 580 INT64 Nullable scale: 0 subtype: 0 len: 8
      01: sqltype: 580 INT64 Nullable scale: 0 subtype: 0 len: 8
    """
  
  @pytest.mark.version('>=3.0')
  def test_1(act_1: Action):
      act_1.expected_stdout = expected_stdout_1
      act_1.execute()
      assert act_1.clean_expected_stdout == act_1.clean_stdout
  
  